Nowadays, lithium batteries are used for several appliances. More and more they are used in high power applications, such as for powering electrical cars, such as battery electrical vehicles (BEVs). A lithium-ion battery can typically provide 400 V and 40 Ah.
At low cell temperatures, i.e. below approx +10° C., these lithium-ion batteries show a degraded performance and have a limited life time, due to the high impedance of the batteries and the risk of lithium plating. Therefore to protect the batteries, heating of batteries, especially in high power applications, is needed. Heating via electric dissipative elements (heaters) has been used to heat the cells directly or via the liquid or air used to thermally manage the cell temperatures. This is however not very efficient since the complete battery systems thermal mass need to heated.
Another method is to use the ripple generated by the electric motor inverter. This may not be possible due to limitations in the inverter or may create EMC (electromagnetic current) problems, nor is it possible during charging.